Apparatus for leather cutting



Sept. 15, 1925.

- R. RODERWALD APPARATUS FOR LEATHER CUTTING Original Fild Aug. 13, 1921 2 Sheets-Sheet 1 Sept. 15, 1925.

1,554,036 R. RODERWALD I I APPARATUS FOR LEATHER CUTTING Original Filed Aug. 13, 1921 2 ets-S ea 2 Fig. /2.

Patented Sept. 15, 1925.

un-tree -STA-TES RUDOLF RODERWALD, QjFjBERLIN, -GEBJM ANY.

APPARATUS non LEATHER CUTTING.

Original application filed August 13, 1921, Serial I No. 492,192.

Divided and this applicationfiled August 7, 1922. Serial "No. 580,274.

To all whom it may concern Be it'known that I, RUnoLr Ronnnwann, a citizen of the Republic o'f Germany, and resident of Berlin, Germany, have invented certain new and useful Improvements in Apparatus for Leather Cutting, of which the following'is a specification.

More particularly my inventionrelates to chains in which metal links and leather links alternateand which form the subject matter of my application filed August 13, 1921, Sen-N0. 492,192,.of which the present applicati'onis a division. The leather links of this chain consist preferably of a V- shaped soft leather plate containing between its degsrawhide plates with holes therein in which pins of the metal links are jour nalled so that the strain of the chain is translated from a metal link to a pair of raw hide plates and'from this pair to the next metal link etc., thepurposeof soft' leather plates being merely to adhere by friction to the wedge-shapedgroove of the pulley.

One of the objects'of my invention is to obtain a chain, which is smooth running even in high speed and also when high power istransmitted. The hitherto known V- or wedge-shaped link chains have the disadvantage (especially at a highspeed) of'lateral shake which is most prominent on vehicles in which the chocks due to uneven road surfaceare transmitted to the chain. This is particularly disturbing on railway rolling stock where the shocks take 'place rhythmically so that there is an aggregating effect in the shaking. Thus when high power is-to be transmittedby means of several'wedgelink chains,thel'atter must be arranged widely apart so that the transmission gear is rendered very costly.

I have found that this disadvantage is caused by inaccuracies in the manufacture of the chains, especially in the manufacture of the V-shaped soft leather plates, which surround the raw hide plates.

In order to avoid this disadvantage and obtain a perfect working of the chain and smooth running of it, I propose to use a milling cutter and to shape the soft leather plates by its working thereon in such a way that the desired shape of the soft leather plates is obtained only by the working of the milling cutter.

Hitherto on the contrary other cutting devices were used and the soft leather plates were formed in'other ways. i

I prefer to form the soft leather plates in one piece as V sha'p'ed parts mentioned above, it=isclear however, that my invention is not restricted to this form, single plates being also adapted to be worked by the milling cutter.

A "further object ofmy' invention is to propose simple constructions 1 ofapparatus in which the soft leather 'parts -lII2Ly' be worked in a-simple and'etfective manner.

In order to fully explain the invention and in what manner the same-isto be performed I have shown severalembodiments of my invention in the drawings, in which is Fig. 1 the top view of -*a-soft -leatherjp'art, Fig. 2 the top view of asoftdeatherdouble plate, Figs. and "4; showth-e side andtop view-of one embodiment of my invention, Fig. 5 is a sectional view on li'ne 5-5 of=Fig. 3, Fig. 6 is the sectional view'of a leather plate worked "by the-apparatus of Fig-s 3 and etjFig. 7 the-sectionalviewofthe-same plate when bent into the form of aflVyFi'g. 8'shows inside elevation a-"detail of a*mo ditication, Fig. 9 a top View of thismodifica tion, and Fig. 10 the detail of this-'modifioation in a sectional viewsimilartothat of Fig. 5, Figs. 11, 12, and l3,respectively the top-, sideand front-elevation of a further modification, Fig. 14 aleather strip worked by this modification, and Fig. 15a sectional view of this strip.

In-the modification illustrated in Figs. '1 to 7 a lower or supporting'frame 1 carries a base plate 8 onWhich; two guides 9 are screwed, the two opposite lyingedgesof the said guides having cut-out portions 10 between which the double stampiirgs -7 are encompassed. "Bevel led'portions '6 (Fig. 5)

are provided in front and behind the cutout portions. ,A fork 11 is pivoted to the base plate 8 about pivots 5 at. both ends of the fork arms 11 which are placed over the stamping 7 near the bevelled portions 6, the fork handle being outside the reach of the stamping. Both the inner edges 12 of the fork arms have bevelled portions forming a continuation of the bevels 6, these bevelled portions together allowing the forming tool 28 to perform its Work. The whole device and the work piece supported thereon are moved under the forming tool by means of a crank handle 4 and the screwthreaded spindle 3. Owing to the method of gripping the piecework the outer edges of the stampings 7 cannot be worked so that the said stamping has the outline shown in Fig. 6. In this case the wedge-like outline cannot extend so far as the two end edges.

In the modification illustrated in Figs. 8 to 10 the guides 9 screwed on the base plate 8 are provided with undercut edges 2 the distance apart of which corresponds to the width between the end edges of the soft. leather do'uble stampings 7 stamped out in its smallest size and laid down flat (Fig. 9). The guideway formed by the guides 9 is fully open at the back through which stampings 7 may be fed. The front ends of the guides are provided with extensions 13 directed towards one another and bevelled at the top according to the wedge faces to be produced by the forming tool. In this construction the plate 8 is used by itself, that is to say is moved under the forming tool 28 with its projections first. Owing to the conditions of working the peripheral speed of the forming tool is greater than the linear velocity of the base plate 8 as soon as the forming tool grips the soft leather stamping, the said tool has a tendency to push it forward at its peripheral speed so that the piece work during the forming process is applied against the two extentions 13. After the forming is completed, the plate 8 is withdrawn, the finished stamping is taken out and the next put in. In this construction of the machine the stampings are gripped at their edges, so that the forming into a wedge may be extended as far as both the end-edges (Fig. 10).

Figs. 11 to 15 illustrate a device by means of which a whole leather strip is worked by the forming tool, this device comprising a stand 14 supporting a base plate 15 provided with a guide for the workpiece. The guide-way may be formed by cutting a groove in the base plate, the depth of the said groove being half the leather strip; it may also be formed by two superposed guide members. The forming tool 28 is above the guide so that the shaft 16 is at right angles to the longitudinal axis of the guideway 17. The said shaft is supported in two bearings 18, 18 between which the rigidly secured belt-driven pulley 19 and the loose pulley 20 are arranged.

The profile of the forming tool is such as to form a rib 22 along the centre of the leather strip 21, the said rib retaining the full thickness of the strip; the wedge shaped wings on both sides of the rib increase outwardly in thickness, the tips of the wings retaining the full original leather thickness. The central rib may however be)done away with. The strip of leather is fed to the forming tool by means of a crank handle 23 the shaft of which is supported in bearings 2st arranged on each side of the guideway, a roller 25 with roughened surface being mounted on the said shaft between the bearingswhich are guided vertically on bolts 26 and pressed downwardly by springs 27 so that the roller is applied on the strip 21 with adjustable resilient pressure.

The strip is moved forward by means of the crank handle until it is gripped by the forming tool 28. The crank handle 28 is rotated slowly in order to hold the strip back and cause it to move slowly. The face of the strip which is later to produce adherence by friction, is suitably roughened while the forming process is proceeding. The hereinbefore described double stampings are stamped out of the finished strip.

Having now particularly described and ascertained the nature of my said invention and in what manner the same is to be performed, I declare that what I claim is:

In an apparatus for cutting wedgeshaped soft leather plates for chains operating with grooved pulleys the combination of a plate with guides having undercut edges between which leather plates are fed from the rear of the machine, inwardly directed extensions at the one end of the guides, the said extensions being adapted to hold the leather in place, a conically formed milling cutter arranged over the guides and adapted to form when operated the leather according to its own conical. form.

In testimony that I claim the foregoing as my invention, I have signed my name.

RUDOLF RODERVVALD. 

